This invention relates to a programmable automatic controller for operating a glassware forming machine having a plurality of functional sections which operate in a timed relationship with one another.
In the past, there has been a great need for a programmable controller for operating such complex machines. The glass forming machine is typically comprised of a plurality of individual sections which are integrated into a single plural section machine fed by a single source of molten glass. The sections are operated in synchronism in such relative phase relationship as to permit the several sections to acquire gobs in ordered sequence from a single gob feeding means. Thus, as one of the sections is taking a gob from the feeding means, another section is delivering a finished article to an output conveyor and the other intermediate sections are engaged in various forming steps intermediate the taking of a gob and the production of a finished ware.
Further, it has been customary in the past to provide two molds in each section of an individual section machine whereby a gob is received in a first mold called the blank or parison mold for the initial process of forming a parison, followed by a transfer of the parison to a second mold called the blow mold for a final blowing of the article. By this means, each section of the machine is operating simultaneously upon two workpieces. In order to control the operation of the various functional components of each section of a glass forming machine, a means must be provided for actuating each of the section elements in a preselected cyclic time format so that the operation of one element does not interfere with, but rather complements, the operation of the other components in the section. In addition, means must be provided for interrelating the timing of the individual sections with respect to a machine standard.
The several functional elements of the glass forming stations of the individual section machine are typically controlled by pneumatic pressure which is controlled by either a mechanical synchronizing means in the form of rotary drums or by an electronic timing circuit. An example of the prior art controller utilizing mechanical synchronizing means is disclosed in Ingle, U.S. Pat. No. 1,911,119. The Ingle glass forming machine is cumbersome and more importantly, is difficult to adjust so that the timing of the operation of the various components of the machine can be varied. An example of the prior art controller utilizing electronic timing circuits is U.S. Pat. No. 3,762,907 issued to Richard M. Quinn et al and U.S. Pat. No. 3,969,703 issued to Kwiatkowski et al, both of which are assigned to the common assignee herewith. Some prior art controllers do not include an easy, simplified means for adjusting the time of operation of the various elements in a machine cycle while the machine is operating and accordingly lacks the flexibility desired in an automatic controller.
In addition, the prior art controllers either provided no means or mechanical switch means for adjusting the time relationship of a section with respect to the machine time. Generally, the section delay means comprised components separate and distinct from the components comprising the means for adjusting the function actuation times. If remote controls were desired for varying either the function actuation times or the section delay time, further separate and distinct components were required for processing the remote commands. Thus, the number of components of the prior art controllers was greatly increased as a result of parallel systems of components performing relatively similar tasks.
A further drawback of the prior art is that the components of the prior art controllers are so numerous and of such size and of such sensitivity that it was not practical to locate the controller adjacent to the glassware forming machine being controlled. Glassware forming machines produce large quantities of heat which tend to disrupt the operation of the components in some of the prior art controllers. Therefore, it was necessary to remotely position the controllers, thus requiring an extremely large quantity of cable, means for shielding the cable from the electrical noise of the environment and means for isolating the controller from the cables. This involved a great deal of expense.
It is therefore an object of this invention to provide a flexible programmable automatic controller for operating a glassware forming machine.
It is another object of this invention to provide an automatic controller having a simplified and efficient means for adjusting the time of the operational functions of a glassware forming machine with a high degree of accuracy while the machine is running.
It is yet another object of this invention to provide an automatic programmable controller that can be placed adjacent to the glassware forming machine it is controlling.
A further object of this invention is to provide an automatic programmable controller having means for adjusting the timing of a section with respect to the machine time.
A still further object of this invention is to provide an automatic programmable controller with means for remotely controlling the means for adjusting the timing of a section with respect to the machine time.
Another objective of this invention is to provide a single means for controlling the remote and local variation of section timing and function actuation in order to minimize the number of components comprising the controller.